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Abelianization of the group of invertible elements in a finite local ring

Let $R$ be a finite local $\mathbb{F}_q$-algebra. Assume that $R\cong R^*$ as left $R$-modules. Are there any known results about the abelianization $(R^{\times})_{\mathrm{ab}}$? (We can factor $R$ be ...
Ehud Meir's user avatar
  • 5,039
1 vote
1 answer
147 views

Do you know a finite unitary reversible ring that is not isomorphic to its opposite? And the minimal with that property?

Do you know a finite unitary reversible ring that is not isomorphic to its opposite? And the minimal with that property? The examples of rings not isomorphic to their opposite that I know of are not ...
José María Grau Ribas's user avatar
6 votes
1 answer
499 views

Do you know which is the minimal local ring that is not isomorphic to its opposite?

The most popular examples are non-local rings and minimal has 16 elements. I am interested in knowing examples of local rings not isomorphic to their opposite.
José María Grau Ribas's user avatar
1 vote
1 answer
52 views

When is $rad(L)[x_1,\ldots]$ radical in $Ker(\varphi_\ast)$?

Suppose we have a local ring $L$ (not necessarily commutative) such that $L/rad(L)$ is a division algebra (here $rad(L)$ is the Jacobson radical of $L$). We clearly have the canonical surjection $\...
John D Evans's user avatar
2 votes
1 answer
241 views

Hochschild cohomology of commutative quotients

Notation: Let $k$ be a commutative local ring and let $HH^{i}(A,N)$ denote the $i^{th}$ Hochschild cohomology $k$-module of a $k$-algebra A with coefficients in an $(A,A)$-bi-module $N$. If $x:=\{...
ABIM's user avatar
  • 5,405
1 vote
1 answer
636 views

Local Rings problem

$\newcommand{\End}{\operatorname{End}}$ let $R$ be a local ring, $\varphi\in \End(R_{R}^{2})$, $\overline{\varphi}\in \End(\overline{R}_{\overline{R}}^{2})$, $\overline{R} =R/J(R)$ , $J(R)$= ...
Samira's user avatar
  • 11